Photographic material for the manufacture of color images



March 30, 1954 L. A. MEEUSSEN ET AL A 2,673,800

PHOTOGRAPHIC MATERIAL FOR THE MANUFACTURE OF COLOR IMAGES Filed Aug. 8, 1947 FIG. I.

7 BLUE-SENSITIVE EMULSION 6. RECEIVING LAYER=DEvELoPMENT NucLEI+DIEFusIONFAsT YELLow COUPLER 5. REcEIvING LAYER =DEvELOPMENT NUCLEH-DIFFUSIONFAST MAGENTA GOuPLER 4 GREEN-sENsITIvE EMuLsION a BARRIER LAYER 2 RED-sENsITIvE EMuLsION I RECEIVING LAYER DEVELOPMENT NEIGLEHDIEPUSIONFAST BLUE-GREEN COUPLER fl SUPPORT v M F O F s s BLUE-SENSITIVE EMuLsION AND GRAINs (DE ELOP ENT NUGLEHD' N A T (YELLow cOuPLER 4 BARRIER LAYER (DEVELOPMENT NucLEI+DIFI=usIONFAsT (MAGENTA COUPLER 2 BARRIER LAYER (DEVELOPMENT NucLEI DIFFUSIONFAST BLUE-GREEN OOuPLER GREEN-SENSITIVE EMULSION AND GRAINS I RED-SENSITIVE EMULSION AND GRAINS FIG. 3.

INVENTORS Louis AchIlles Meeussen A berI ell y AT TORNE YS supports.

these layers may becoated on onesupport.

Patented Mar. 30, 1954 UNITED STATES PATENT OFFICE 'PHOTOGRAPHIC"MATERIAL 'FOR THE MAN UFACTURE 0F COLOR'IMAGES --1 This invention relates to the production of color images by means of diffused-silver halide.

-It is an improvement of the process disclosed-in Patent 352,015, according to which photographic reversal images-are obtained when the silver halide which-was nota ffe'cted by light during=an exposure of=a silver halide layer, is caused to diffuse into and to be reduced in a receiving layer, which isnot sensitive 'to light. In applying thisprinciple, the sen'sitive layer and the receiving layer may be coated onto two separate After exposure, the sensitive layer is pressed upon th'e receiving layer in 1 the presence of substances; necessary for producing the posi- 'tive reversal image, either by direct reaction 'with the :difiuse'd silverhalideor by induced "reaction or-bycatalytic rea'c'tion.

Instead of using separate supports for'thesensitive layer and for the receiving layer, both Substances whichspeed up the reduction of silver halide not afiected by the light in the presence of a silver halide solvent i. e. reduction and crystallisation nuclei forsilver--halide,'"and substances capable offormingsuch nucleiby reaction with silver halide, may be mixed in" the sensitive-layer.

-In either case, besides'silverimages, alsocolor images are obtainable directly, for instance, a receiving layer containing an adequate dyestuff 'for the silver bleaching out process maybe used.

This dyestu if is bleached'out in proportion to the silver of theireversalimagein the'receiving layer and in this way-a colorimage' is produced.

The reversal image may also bef'ormed by-color development. ing the exposed material in a usual developer, allowing the not-reduced :silvertodifiuse into and to be reduced in the receiving layer, re-

-halogenizing the secondary image and finally re-developing the halide thus formed in a color developer. After removing the two silver images,

a colored-secondary image is left.

The diffusion and the color-image formation can alsobe carriedout" in -a single treatment. To this end, the material is -washed-after the first development as usual in order to altogether remove the developer. It is then treated in a color developer containing-a silver salt solvent. The

not-reduced silver salt diffuses intothe receiving layer formingtherein both a" silver image and a-color imagebythe'actioniof the substances accelerating the'reduction. To those skilled in theartpf' color "photography, it is ob- =viousithat thel-color-fcouplers may be present in the color cleveloper o'r "m me-receiving layer.

One method consists in develop- 5-? :1 Claim. (c1. 95-2) added to the primary developer.

In-case the coupler in the receiving layer is diffusion-fast, the silver salt solvent may be The diffusion of the not-reduced silver halide consequently already takes place after the first development in such a way that a primary negative image is termed in the emulsion layerand at the same time a secondary positive image in the receiving layer. After washing, the two silver halide "images are re-halogenizedand re-developed in a color developer; now a negative silver image is formed in the-emulsion layer anda color image simultaneously with a positive silver image in the receiving layer.

It isto be noted that this process'only yields single-color images.

It is an objectof-the present invention to provide new photographic processes forthe manufactureof-color images by diffusion and reductioninthe presence-of a silver halide solventof thesilver halide not affected by light of the light-sensitive layer in a not-sensitive receiving layer containing substances which accelerate the :reduction of silver halide: not affected .by light :.si'lver halide substances capable .of producing :such nuclei :by reaction with silver halide.

such-as reduction and crystallisation nucleifor Itiis anotherobject of the presentinventionto provide a new. photographic material. adapted for :nse. in the above process.

Further objects will appearifrom the following description.

;.In .order to obtain vmulti-color reproduction, at least .two1.single=.colored part-images are, required,=which.. means that forcolor photography .according to our .present process,.a material :theoretically should consist ofat. least two,. preferably three emulsion layers and also .of their respective receiving :layers. Since one of the emulsion layers necessarily is in contact with two receiving layers, the not-reduced silver salts of this emulsioncan diffuse into two, diiferent receiving layers i. e. two different colored positive images maycorrespond to one part-image which results in an incorrect colour rendering.

'It was found that by' providing a barrier layer all undesired diffusion from an emulsion layer into areceivinglayer may be avoided. g

- 'A 'photographic' multi-layer according to our invention which allows obtaining multi-color images according to thediffusion principle in a simple and positive way, contains the usual sensitive layers, correspondingreceiving layers and at least onebarrier layerwhich forms the separation betweena sensitivelayerand an adjacent receiving layer. These barrier layers are characterized thereby that they contain substances which check the diffusion of the silver salts either by catalytic action or by chemical reaction. Such substances are developmentnuclei, such as colloidal silver, silver sulphide, fogged silver halide emulsion and others, as described in Patent 2,352,014. The difi'used salt probably will be decomposed, by the catalytic action of the development nuclei, to metallic silver which is precipitated in the barrier layer and subsequently is removed simultaneously with the silver image.

The barrier action may be obtained also by using substances which precipitate the dinusing complex silver salts, such as for instance the known photographic stabilizers having a reactive hydrogen atom in an ammoor a mercapto group.

The thickness of a barrier layer required, depends upon diiferent factors such as e. g. the nature and the concentration of the development nuclei and precipitating substances, the concentration of complex silver salts, the nature of the developers used whilst reducing the diffusing silver salt etc.

As set out before, the barrier layer is arranged between an emulsion layer and a receiving layer.

,This arrangement, however, can be varied within wide limits. A receiving layer e. g. may be functioning as barrier layer which is of primary importance for a material wherein the two receiving layers of two succeeding sensitive layers are coated in superposition in between the said sensitive layers. In this case, the barrier action of the receiving layers may be increased by correspondingly varying the thickness of the layers or by a greater concentration or development nuclei and precipitating substances. Sometimes, it may be useiul to arrange an extremely thin barrier layer between the two receiving layers.

Of particular value is a layer containing both the sensitive salts and the receiving substances according to applicants French Patent 13,013. When three such layers are used, it may sufiice to apply two barrier layers between the tnree layers. The process can be simplified further by an addition 01' the dye-stuns of the filter layers or of the anti-halation layers in one or more layers at will.

Treatment of photographic material according to this invention is simple and can be carried out by any person slightly skilled in the art of photography. For instance, when color development is used, the three primary part images are developed in a usual photographic developer. Next the remaining developer is completely removed by thorough washing. The material is further treated in a color developer containing a solvent for silver salts as fully described in Patent Number 2,352,014.

In this developer, the remaining silver salts diffuse from every emulsion layer into the corresponding receiving layer and are reduced upon the development nuclei; simultaneously the oxidization products of the developing agent are coupled with the diffusion-fast color coupler, which is contained in every receiving layer. In this way, dyestufis are obtained which correspond to the optical sensitization of each sensitive emulsion layer. After removing the metallic silver, the color image appears.

,, In the process according to the silver bleach- 4 ing-out method the material is treated correspondingly.

The invention, as a matter of fact, is not limited to the use of the silver bleaching-out method nor to the process of the color development. All other processes, however, applied in color photographic technics may be used separately as well as simultaneously and at will. In this connection, a three-layer material may be used wherein the receiving layer of the blue-sensitive layer contains a yellow dyestuff, which afterwards is destroyed according to the silver bleaching-out process, whilst both the other receiving layers contain diffusion-fast color couplers which by color development produce a color image.

The color images obtained by color development are distinguished by a particular purity of colors. The reduction of the diffusing silver salt forms metallic silver in an extraordinarily finelydivided state, so that the dyestufi obtained produces a favourable absorption curve.

The new material can be used for the production of either negative images or positive images, transparent images as well as of images to be viewed by reflected light.

Being included in the receiving layers, the different diffusion-fast dyestuffs or color couplers are separated from the sensitive emulsion so that any undesired influence of these substances upon the photographic emulsion is prevented.

This invention will further be described in detail, and by way of examples, with reference to the accompanying drawing wherein Figs. 1. 2 and 3 are diagrammatic sections of different photographic materials employed in accordance with the invention as described in the following examples.

Example 1 A material is used according to Fig. 1, wherein the following layers are arranged on the support:

After exposure, this material is developed in the following bath (1):

Metol g 1 Sodium sulphite (cryst.) g 10 Hydroquinone g 3 Sodium carbonate (cryst.) g 100 Potassium bromide g 2 Water ccs l 1000 It is then washed and treated in the following bath (2):

Sodium sulphite (cryst.) g '5 N,N-diethyl-p-phenylene diamine hydrochloride g 4 Sodium thiosulphate (cryst.) g 3 Sodium carbonate (cryst.) g Water ccs 1000 Both a silver image and a color imageiare formed upon the development nuclei in the layers i, and 6, which images are positive in respect to the adjacent emulsion layer. It was not necessary to provide a barrier lay-er between the receiving layers 5 and 6, the concentration of the development nuclei being sufiiciently high. In this case, the diffusing silver salts from the layers i and l are wholly reduced. Consequently, no diffusion from the layer 4 into the layer '5 or from the layer i into the layer 5 takes place.

After washing and removing both the remaining silver salt and the silver image formed, a pure color image is obtained.

Example 2 A material according to Fig. 2 containing the following layers upon the support is used:

This material, after exposure, is developed in the first bath of Example 1, washed and colordeveloped in bath 2 until the color images formed in the grains are of suificient intensity. The remaining silver salts and the silver formed, are removed after washing in the known manner.

Example 3 The material is the one described in Example The diffusion is not induced while developing in bath 2, but during the first development by adding 2 g./liter of sodium thiosulphate to the bath 1. Whilst developing in this developer the negative silver images are formed in the layers and positive silver images in the grains. After fixing and washing, the silver of the image is re-ha-logenized in the following bath:

Potassium ferricyanide g 25 Potassium bromide g Water ccs 100 The image is washed and re-developed in a developer which contains a known cyclic diamine as reducer. During this development silver images are formed in the emulsion layers and both silver images and positive color images in the grains which contain the color components. After washing and removing the silver, a color image is left.

Example 4 A material is used according to Fig. 3 containing the following layers upon the support:

( 1) A layer which contains development nuclei and a diffusion-fast blue-green azodyestuff,

(2) A red-sensitive silver halide emulsion,

A barrier layer containing a binding agent and development nuclei,

A layer, containing a binding agent, de-

velopment nuclei and a magenta dyestufl,

A green-sensitive silver halide emulsion,

A barrier layer as described above,

(7) A layer, containing a binding agent, de-

velopment nuclei and a diffusion-fast yellow azodyestuif,

(8) A blue-sensitive silver halide emulsion.

After exposure, this material is treated in the following bath:

Metol g 2 Sodium sulphite (cryst.) g 50 Hydroquinone g 6 Sodium carbonate (cryst.) g Potassium bromide g 2 Sodium thiosulphate g 2.5

Water ccs 100 Negative silver images are formed in the emulsion layers and positive images in the layers 1, 4 and 1. After fixing and washing, the material is treated in a bleaching bath whereby the azodyestuffs in the layers I, 4 and l are bleachedout according to the silver bleaching-out process. The silver is then rehalogenized and removed by fixation.

Various changes may be made in the process and materials described above without departing from the principle on which the invention is based.

We claim:

A photographic material comprising in superposition:

I. A support; 2. A layer containing a diffusion-fast blue-green color former capable of coupling with the oxidation products of a primary aromatic amino developer to form a dye image and a substance selected from the group consisting of heavy metals, insoluble sulfides of such metals and fogged silver halide emulsion; 3. A red-sensitive silver halide emulsion layer; A barrier layer containing a substance selected from the group consisting of heavy metals, insoluble sulfides of such metals and fogged silver halide emulsions; 5. A. green-sensitive silver halide emulsion layer; 6. A layer containing a yellow diffusion-fast color former capable of coupling with the oxidation products of a primary aromatic amino developer to form a dye image and a substance selected from the group consisting of heavy metals, insoluble sulfides of such metals and fogged silver halide emulsion; 7. A blue-sensitive silver halide emulsion layer.

LOUIS ACHILLES MEEUSSEN. ALBERT BELLAY.

OTHER REFERENCES Sciiet Ina. Phot., 2nd series, vol. 13, July- August 1942, pages 151--152. 

1. A SUPPORT;
 2. A LAYER CONTAINING A DIFFUSION-FAST BLUE-GREEN COLOR FORMER CAPABLE OF COUPLING WITH THE OXIDATION PRODUCTS OF A PRIMARY AROMATIC AMINO DEVELOPER TO FORM A DYE IMAGE AND A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF HEAVY METALS, INSOLUBLE SULFIDES OF SUCH METALS AND FOGGED SILVER HALIDE EMULSION;
 3. A RED-SENSITIVE SILVER HALIDE EMULSION LAYER;
 4. A BARRIER LAYER CONTAINING A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF HEAVY METALS, INSOLUBLE SULFIDES OF SUCH METALS AND FOGGED SILVER HALIDE EMULSIONS;
 5. A GREEN-SENSITIVE SILVER HALIDE EMULSION LAYER;
 6. A LAYER CONTAINING A YELLOW DIFFUSION-FAST COLOR FORMER CAPABLE OF COUPLING WITH THE OXIDATION PRODUCTS OF A PRIMARY AROMATIC AMINO DEVELOPER TO FORM A DYE IMAGE AND A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF HEAVY METALS, INSOLUBLE SULFIDES OF SUCH METALS AND FOGGED SILVER HAILDE EMULSION;
 7. A BLUE-SENSITIVE SILVE HALIDE EMULSION LAYER. 